Percutaneous access to the cardiovascular system is used to diagnose, evaluate, and treat a variety of conditions. A typical procedure involves passing a wire guide through an opening in a patient's skin which connects with a vascular structure such as a vein or artery. The wire guide can then be passed through the cardiovascular system to a location of interest within the patient. Once the wire guide has been appropriately positioned, a catheter can be passed into the patient and guided by the wire guide to a location where the procedure is to be performed. Angioplasty, imaging, and the placement of stents, grafts, filters and other devices, are common procedures which are performed according to variations of the above general technique. It is also common to use percutaneous access for the placement of catheters which deliver fluid at an intraluminal treatment site. Devices known as infusion catheters are commonly used to deliver a therapeutic treatment fluid such as a thrombolytic agent to a thrombus within a vein or artery.
A wide variety of infusion catheter designs are known and commercially available. A typical infusion procedure may involve leaving an infusion catheter within a patient for period of time while treatment fluid flows from a fluid supply into the infusion catheter, and thenceforth into an intraluminal space. In the case of dissolving a thrombus, known generally as “thrombolysis,” thrombolytic agents effused from a catheter into an intravascular site chemically dissolve material of the thrombus. A variety of factors can influence how long a thrombolytic procedure lasts. Size of the vascular structure which includes the thrombus, the type of thombolytic agent, geometry and/or age of the thrombus, and still other factors such as the distance fluid must travel from an extraluminal fluid supply to the treatment site, can all affect the selection and administration of a particular procedure.
A variety of thrombolytic agents are well known and widely used. It is generally desirable to avoid overusing thrombolytic agents, as such materials tend to be relatively expensive. If used in excess, thrombolytics can negatively affect parts of a patient's body outside of an intended treatment site, such as by causing bleeding. In response to these and other concerns, a variety of designs which use not only a thrombolytic agent but also some mechanical strategy to break up a thrombus have been proposed. Cutting implements, suction devices, systems using ultrasonic energy, and still others have found a certain degree of commercial success. These conventional strategies, however, tend to have a number of disadvantages. Among these is the common requirement of a power source to spin a catheter from outside a patient's body, generate ultrasonic energy, aspirate tissue, or for other purposes.